The present invention relates to a combustion chamber for a gas turbine engine, more particularly such a combustion chamber having a counter-flow arrangement to minimize harmful pollutants in the exhaust gases.
U.S. Pat. No. 4,040,252 to Mosier et al. discloses a combustion device for a power plant which comprises a first enclosure in which a fuel/oxygen mixture is ignited and burned, and a second chamber through which the exhaust gases from the first combustion chamber pass. The primary combustion air is added to the first chamber upstream of the ignition device, while additional air is added to the first combustion chamber downstream of the combustion device. Additional air is added to the exhaust gases after they have passed through the second chamber portion. The gases pass through the first chamber in a direction generally opposite from which they pass through the second chamber.
In this device, as is typical of the known counterflow combustion chambers, a dilution gas, which may be part of the intake air, enters the first chamber portion to dilute the exhaust gases of combustion. As a result of this addition of dilution air, the fuel/oxidizer mixture becomes leaner and the combustion process is slowed. This promotes the formation of nitrogen oxide in the exhaust gases, thereby increasing air pollution.